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If
the problem is Carbon Dioxide, wouldn't it make more sense
This patent pending business method involves a new kind of atmospheric carbon dioxide emission abatement credit that actually prevents the creation of gaseous CO2 from coal (and/or other fossil fuels), rather than merely trading CO2 offsets created by other indirect means. Carbon emissions from coal can be reduced by almost 80% by simply repurposing and adapting an existing 150 year old technology, namely the coke oven, still used to derive coke from coal for use in smelting iron into steel. An updated thermal volatile extraction (TVE) process can now instead be used to separate the volatile gases from coal for energy, while leaving the carbon as a solid in the form of coke. The resulting solid carbon can be used as a building material, industrial feedstock, or simply buried. The remaining carbon emissions from coal could be completely eliminated using another existing technology, thermal decomposition of methane (TDM), to separate the hydrogen from methane, leaving solid carbon by vapor deposition. Coal currently sells for $10 to $50 per ton in the U.S. (the range has been as large as $6 to $66/ton in the last two years). From 50% to 92% of the total weight of coal is carbon, but each CO2 molecule weighs 3.6 times more than one carbon atom so typical coal might produce around 3 tons of CO2 if burned. About 1/4 of the energy is in the hydrogen, so the same energy would appear to require almost 4 tons of coal, or an extra 3 tons of coal to achieve zero CO2 emissions:
Thus, at a price per ton for CO2 roughly equal to the price per ton of coal, CO2 emissions from coal can be completely eliminated. But now add the efficiency gain of burning the gas in a combined cycle power plant, instead of solid coal, and it might only require twice as much coal to go to zero; at a CO2 price of less than half the cost per ton of coal! This calculation only considers comparative fuel cost and does not include the capital cost of the coke oven and gas power plant, but if anything it appears that these units together may be cheaper than building a new conventional coal plant. A reduction of about 78% in CO2 emissions can be achieved by means of the first stage TVE alone, using basic coke oven type technology that yields a mixture of hydrogen, methane and carbon monoxide, plus BTX liquids and coal tar, along with solid coke. The TVE process is energy neutral at 800 to 1000 degrees C, i.e. the reaction itself does not actually consume any energy beyond the sensible heat required to maintain the vessel at temperature. Simply burning the coke oven gas in a boiler to produce electricity would yield approximately 31% of the high heating value that would have been produced by burning the coal, while emitting only 7% of the CO2. Doing so would apparently require about 320% of the coal to produce the same electricity, while emitting only 22% of the CO2 as burning one ton of coal. But again, if the gas is instead used in a combined cycle power plant the efficiency could almost double, meaning that it will only require slightly over one and a half times as much coal, or say an extra 60% to reduce emissions by almost 80%.
The overall process could be made fully carbon-neutral, thereby emitting zero CO2 from coal, by adding a second stage, whereby the methane, and small amounts of other hydrocarbon liquids, are converted into pure hydrogen and carbon using TDM. The solid carbon from vapor deposition can be used as a feedstock to manufacture carbon fiber materials. At the completion of the full decarbonization process virtually 100% elimination of CO2 emissions from coal could be achieved while delivering 26% of the high heating value that would have been derived from burning the coal. This would theoretically require 380% of the coal that would have been burned to produce the same energy. However, with combined cycle gas combustion technology this could mean less than double the coal to take CO2 emissions to zero. Global CO2 elimination credits will be fungible. So, the first place to find the cheapest coal for the most attractively priced credits will be offshore coal plants. The same approach could also be applied to all fossil fuels, and the same CO2 credit trading market can be extended to other fossil fuels by leveraging TDM and similar technologies. The theoretical net energy yield for TDM is 55%, so decarbonizing natural gas would effectively double the cost of energy from gas, while decarbonizing oil would be expected to fall somewhere between the cost of coal and natural gas. v
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